Emanuel Steward, earnest yet easygoing, proved rough and tough wasn’t the only way to win in boxing.

With a twinkle in his eyes, a smile on his face, and a soothing voice, Steward developed unique bonds in and out of the ring with a long line of champions that included Thomas Hearns, Lennox Lewis, Oscar De La Hoya, and Wladimir Klitschko.

Steward, owner of the Kronk Gym in Detroit and an International Boxing Hall of Fame trainer, died Thursday. He was 68. His executive assistant, Victoria Kirton, said Steward died Thursday at a Chicago hospital. She didn’t disclose the cause of death.

“With the loss of Emanuel Steward, we have lost a true Detroit icon,” Detroit Mayor Dave Bing said. “Emanuel Steward embodied our city’s toughness, our competitive spirit, and our determination to always answer the bell.

“We are grateful for Emanuel Steward’s many contributions to our city and his impact on generations of young people.”

In the early years at Kronk, most of his fighters were black. In recent years, his melting pot of boxers included a Ukrainian heavyweight, an Irish middleweight and scores of young men from Eastern Europe, Latin America, and the Middle East.

Steward was inducted into the International Boxing Hall of Fame in 1996.

“It brings me great grief and sadness to hear of the passing of one of the best and most respected trainers of this era,” De La Hoya said. “I learned a lot from him during our professional relationship and I will be forever grateful for his help during that time. We were also friends and I know I am going to miss him as so many others will, too. He was an important part of our boxing community.”

Lewis, a former heavyweight champion, was trained by Steward from 1994 to 2004, a period which included victories over Evander Holyfield and Mike Tyson.

“This has been a very tragic year for the boxing world, but today we’ve truly lost one of its crown jewels,” Lewis wrote on his official website. “Manny always told me I was the best, but the truth is, he was the best and I’m grateful, privileged and honored to be counted among his many historic successes.

“Manny was giving, selfless, compassionate and stern,” Lewis said. “I’m proud to have had him in my corner for so many years. … I’ll miss his smile, his frank no-holds-barred truthfulness and our discussions on boxing and life.”

Read it at CBS News.